Rotary engine



Jai.. 17, 1933.

H. E. KEMP-ron ROTARY 'ENGINE Filed Sept. 14, 1929 Patented Jan. 17,1933 UNITED s'rA'Es a; 'r n. or cIIIcneo, ILLINOIS, .assIeNoa Toru'rmnr. rm

60mm, 0l' CHICAGO, ILLINOIS, A. CRPORATION OF ILLINOIS 'normar ENGINEApplication mcd September 14, 1929. Serial No. $92,638.

The present invention relates to improvements in rotary engines, and hasEartlcular reference to rotary gear pum s of t e general t pe disclosedin my copen ing application 5 er.-No. 319,217, filed November 14, 1928.

Gear pumps ofA this type commonly comprise a ody having a cylindricalchamber open at one end, spaced mlet and discharge passages opening intothe chamberrotary 1 ear means in the chamber for carrymg iiuld rom onepassage to the other, and a removable cover plate for closing the outerend of said chamber. In practice, the gear means is confined againstendwise movement between the inner end of the chamber and the coverplate, and close end clearances are provided to maintain the necessaryseal between the passages.

Heretofore, considerable diliculty has been 2 encountered 1n reventingleakage between the body and tllfe cover plate, articularly when li htfluids, such as light oils, are handled. a result, it is extremelydiilicult to maintain the iuid under high pressures, and

where oil is handled, the leakage creates a bad lire hazard.

A. gasket is commonly interposed between the body and the cover platefor the purpose of preventing leakage. While leakage can be 3substantially prevented by the use of a thick gasket, such gasket is notcommercial and is unsatisfactory. Thus, a thick gasket is compressibleand is subject to change upon changes in temperatures, and hence willnot maintain the necessary end clearances, thereb resulting in bindinofthe relatively mova le parts. This di culty is particularly pronouncedin small oil pumps where the clearances are especially small. If thegasket 0 is fibrous, it is practically impossible to prevent leakage bycapilla action. A thin asket on the other hanld7 will not preventeakage.

The primary obj ect of the present invention therefore resides intheprovision of a new andimproved packing adapted to prevent leakagebetween the body and cover plate of a gear pump or engine withoutaffecting the end clearances of the relativel movable parts and withoutlowering the e ciency of the pumping action.

A more specific object resides in the provision of novel means forpreventing leakage between the body and cover plate of the pump, saidmeans comprising a thin metal gasket, and means for automaticallyventing opposite sides of said gasket to the suction side of the pump soas to prevent leaka e.

Further objects and advantages w1ll become apparent as the descriptionproceeds.

In the accompanying drawing, Fig. 1 is an axial fragmentary sectionalview of a pump embodying the features of my invention.

Fig. 2 1s an end view of the pump with the cover plate and gasketremoved. A 55 Fig. 3 is an inner face view of the cover plate.

Fig. 4 is a fragmentary sectional view taken along line 4-4 of Fig. 2.

While the invention is susceptible of various modilications andalternative constructions, I have shown in the drawin and will hereindescribe in detail the pre erred embodiment, but it is to be understoodthat Il do not thereby intend to limit the invention to the specificform disclosed, but intend to cover all modifications and alternativeconstructions falling within the spirit and scope olf the invention asexpressed in the appended c aims.

' While the invention is not limited in its applicability to anyparticular type of pump, it is particularly adapted for and is thereforedescribed in connection with a rotary gear pump. In the presentinstance, the pump constituting the exemplary embodiment of theinvention comprises a suitable casing 10 which preferably is cylindricalin form to grovide an inner cylindrical chamber 11.

uitable inlet and outlet passages 12 and 13 9 4 respectively, are formedin the casing 10 and a removable head or cover plate 16 suitably llildin place by means o f a plurality of bolts Rotatably mounted inthechamber 11 and i in close peripheral bearing contact therewith is arotor 18 having a sultable coaxial drive shaft 19 projecting rearwardlytherefrom` through the bearing 15 for connection to a between the rotor18 an suitablesource of power (not shown). In the present instance, therotor 18 is formed on its front endwith a plurality of peripherallyspaced internal gear teeth or vanes 20 separated by interdental spaces21. Rigidly mounted in the inner end of the chamber 11 in bearingengagement with the inner end of ,the rotor 18 isa suitable bearingplate 22.

The free outer ends of the vanes 20 bearagainst the cover plate 16.

Eccentrically related to the rotor 18 and in mesh with the vanes 20 is ainion 23 having suitable teeth or vanes 24. he pinion 23 is mounted forrotation on la pin 25 projecting inwardly from the cover dplate 16.Disposed the pinion 23 is a crescent cut-off partition 26 whichreferably is formed integral with the cover plate 16.

It will be evident that upon drlving of the rotor 18 inacounter-clockwise direction, fluid, such as oil, will be carried fromthe inlet side 27 to the outlet side 28 of the chamber 11. It isessential in order to obtain anefficient action and to maintain a highpressure in the outlet side 28 of the casing 10 that leakage past therelatively movable parts be substantlally prevented.- Hence relativelysmall end clearances are provided between the rotor .18 on one hand andthe plates 16 and 22 on the other hand.

An imiortant feature of the present invention resi es in the provisionof means for preventin the outward leaka e of Huid between the enxof thecasing 10 an the cover late 16. To this end, a asket 29 is interposedtween these parts. referably, th' gasket 29 is made of a thin and butslightly compressible material, such as co per, so'that the proper endclearances will e maintained.

Formed in the end face 30 of the casing 10 is an annular groove 31. Asimilar groove 32 is formed directly opposite the groove 31 in the innerface of the cover plate 16. The opposed grooves 31 and 32 open to theopposite sides of the gasket 29,'and serve to collect any iluid tendingto leak past the gasket. These grooves obviously `will interrupt anyleak lines that ma tend to form along the gasket, and any tluicollecting therein will tend to improve the seal. A suitable number oftenace apertures, in the present instance one ape-r- It will be vevidentthat I have provided-a novel means for preventing leakage of fluid fromthe pump chamber outwardl between the bodyl' and the cover plate. ismeans althoug serving to prevent leakage, does not inuence'the size ofthe end clearances between the relatively movable parts. As a result'the pump is always ellicient in operation. The packing means isparticularly ada ted to small oil pumps'in which relative y smallclearances are provided' and where the leakageof oil .is tionable duetothe Iresu ber 11 are hermetically sealed and slnce the properclearances are obtained, relatively high pressures can be easilymaintained in the outlet passage 13.

vI claim as my invention:

1. A pump comprising, in combination, a casing having a chamber open atone end and having spaced inlet and discharge passages opening to saidchamber, a removable cover plate closing said chamber, rotary fluidtransmission-means in said chamber, and a thin metallic gasketinterposed between said casing and said cover plate, said casing andsaid cover plate beingA formed respectively with opposed shallow annulargrooves opening along `opposite sides of said gasket,l said gasket belngformed with an aperture establishing communication between said groovesand 1nto screw threaded engagement with said casing for securing thecover to the casing, opposed annular grooves formedrespectively in saidcasing and said cover spaced from said screw device apertures andopening to said packing, means establishing communication between saidgrooves, and a ,duct connecting one of said v4grooves tosaid inletpassage.'

artlcularly objecting fire hazard.Y Since the parts forming the pumpingcham-- communication betweenl 3. A p1.np comprising, in combination, a.casing having a chamber o en at one end and having spaced inlet andischarge passages opening to said chamber, a removable cover closingsaid chamber, rotary fluid transmission means in said chamber, a packinginterposed between said casing and said cover, an

annular groove formed in one of the parts contacting with said asket andopening peripherally to said gas et intermediate the peripheral marginsof said gasket, and a duct connecting said groove to said inlet passage.

4. A leak-proof seal for a ump or the like having a hollow open-si edcasing, a closure member therefor and headed screws passing throughlcircumferentiall spaced apertures in said closure member or securin saidclosure member tothe casing, comprlsing, in combination, continuouscomplementary and opposed annular grooves formed in the meeting faces ofsaid casing and closure member and spaced from said screws, a relativelythin and substantially incompressible packin member interposedbetweensaid meeting aces and separating said grooves, and one or morepassageways connecting said grooves.

In testimony whereof, I have hereunto aiixed my signature. l

HERBERT E. KEMPTON.

